A colony of 300 female cebus monkeys are persistently reinoculated at 6-month intervals; 225 receive Herpes Simplex Virus Type II, (HSV2), and 75 receive control material. Samples are taken prior to and after each inoculation to determinne whether infection and/or cytological anaplasia occurs. Approximately 50 percent of all virus inoculated females become infected at each inoculation. All animals which have received 3 or more inoculations have become infected one or more times. The incidence of virus shedding, lesions and herpes cytology (giant cells with intranuclear inclusion bodies) is lower after reinoculation than after primary inoculation. No animals have developed cervical carcinoma. However, 5 virus inoculated have had persistent cytological changes of moderate anaplasia and 8 virus recipients have developed persistent mild anaplastic changes. Control animals have not developed persistent changes of anaplasia. HSV-2 has been isolated from the pooled lumbosacral dorsal-root ganglia from 1 virus-infected female by in vitro explant cocultivation with MA 184 tissue.